1. Field of the Invention
The invention relates to a device for energy recovery for a large diesel engine, specifically a large diesel engine on ships and in land-based plants.
2. Description of the Related Art
Electrical consumers on ships are usually supplied with electric energy from an on-board electric network. To lower operating costs, it is usual to generate electric energy from waste heat of a marine engine aided by a four-pole alternator to feed said energy into the on-board network.
It is known from DE 10 2006 040 857 A1 to operate a steam turbine with heat energy of the exhaust gases of a large diesel engine and convert mechanical rotational energy generated by the steam turbine into electric energy in a current generator. The generated energy can then be fed to the on-board network. This publication additionally discloses feeding part of the exhaust gases directly to a power turbine coupled the current generator.
WO 2006/072791 A1 discloses an energy recovery system for a marine diesel engine wherein a current generator is coupled to a steam turbine and a power turbine. The two turbines are connected in series and coupled with an end of the generator shaft. An energy recovery system is additionally described wherein the current generator is positioned between the two turbines. Depending on the particular arrangement, various complex gears for coupling the turbine shafts with the input shaft of the four-pole current generator are required, since the rotational speeds of the individual components differ from one another.